Newly emboldened Republican lawmakers in Iowa and New Hampshire have sharpened their focus on blocking gay marriage rights, thrusting a wedge issue into the spotlight just as candidates start wooing voters in the most important states on the presidential primary calendar.

The debate over the divisive social issue has recently neared a boiling point in both states, even before the Obama administration decided to oppose the Defense of Marriage Act. Already there have been packed state house hearings in New Hampshire, Iowa Supreme Court judges ousted and groups threatening oaths for presidential hopefuls.

“It was never a plan to make it into a national issue, but it just seems like the timing is right,” Kevin Smith, executive director of the socially conservative think tank New Hampshire Cornerstone, told Roll Call.

Iowa and New Hampshire are among just five states and the District of Columbia that allow same-sex marriage because of court rulings or votes by their state legislatures. (Maryland appears to be close behind.) And following massive GOP gains in the Iowa and New Hampshire state houses last November, both state legislatures are moving aggressively to curtail same-sex marriage.

In New Hampshire, where the GOP now holds veto-proof majorities in the House and Senate, legislative leaders recently decided to postpone action until next January on a high-profile bill to repeal same-sex marriage rights. The debate, which clogged hearing rooms and dominated Granite State headlines earlier in the month, is now scheduled to re-emerge at roughly the same time as the state’s first-in-the-nation presidential primary.

Cornerstone will ask each Republican presidential candidate to sign a pledge agreeing marriage should be between one man and one woman.

“Why not try to leverage the influence of the candidates to get them to declare their support for traditional marriage?” Smith said. “If you have a candidate saying they’re not willing to oppose same-sex marriage, I think they’ll have a problem. ... We have a wide membership list. We’ll certainly let them know.”

“I think there is real momentum,” he said of the push to fight gay marriage. His group, the Iowa equivalent of Cornerstone, is already hosting 2012 candidates for a speaker series, and marriage is suddenly back on the radar.

“I support the notion that we, as a society, should continue to elevate traditional marriage, that it should remain as between a man and a woman, and that all other domestic relationships are not the same as traditional marriage,” Republican Tim Pawlenty, the former Minnesota governor, said when addressing the audience at the Family Leader series this month.

It’s a marked shift from the 2010 election cycle, which largely ignored social issues. The timing in some ways feels more like 2004, when national Republican operatives made sure key swing states had marriage initiatives on the ballot to drive turnout among socially conservative voters, helping the GOP and then-President George W. Bush.

In 2012, gay marriage “will truly energize a segment of the conservative base,” predicted Republican Mike Huckabee, the former Arkansas governor who is considering a repeat White House bid.

Huckabee told Roll Call last week that it may not be “the hot, dominant issue for the next year and a half,” but the conservative groups aiming for national attention are hoping to keep marriage in the headlines.

While the New Hampshire Legislature (under different leadership) previously legalized same-sex marriage, the practice is allowed in Iowa because of an April 2009 state Supreme Court decision.

Vander Plaats recently led efforts to oust the three state Supreme Court justices blamed for the decision, but he concedes full repeal is unlikely. While the Iowa House chamber is now controlled by Republicans, state Senate Majority Leader Mike Gronstal (D) has repeatedly vowed to block any effort to pass a constitutional amendment banning same-sex marriage.

“There is a noisy group of people that wants to change this,” Gronstal told Roll Call. “I think that the minority is growing louder, but I don’t think their numbers are growing.”

He acknowledged that some conservative groups would leverage the influence of the presidential contest to push the cause.

“Both Iowa and New Hampshire get lots of folks that say, ‘Here are two places where it’s our opportunity to influence the national debate.’ We’re fairly used to that here,” he said. “I certainly think there will be some activity in Iowa on that front by various groups.”

Indeed, Gronstal noted that Republican state lawmakers are testing creative ways to block gay couples from marrying. They’re currently debating a bill that would block local officials from issuing marriage licenses to gay couples.

Vander Plaats suggested that Republican Gov. Terry Branstad could address the issue with an executive order. Branstad, who unseated Democratic Gov. Chet Culver last fall, has said he wants voters to be able to decide the marriage issue.

Any legislative action would presumably happen in the coming months, just as presidential candidates push their campaigns into full gear.

The re-emergence of social issues obviously helps some prospective presidential candidates more than others.

There’s Huckabee, an ordained Southern Baptist minister who titled the first chapter of his new book “The Most Important Form of Government is a Father, a Mother, and Children.”

“The family structure that made this country the most powerful and prosperous in the history of the world — father, mother, children — is under assault today as never before,” he wrote, later adding: “Still, I believe that we’re in denial about potential problems as we see more and more homosexual couples raising families. It will be years before we know whether or not our little guinea pigs turn out to be good at marriage and parenthood.”

And fellow cultural conservative Rick Santorum, a former Pennsylvania Senator who is among the most aggressive early prospective presidential candidates, said he wasn’t yet aware of the same-sex marriage debate in New Hampshire but welcomed a discussion on the issue.

“Family is vitally important to the future of our country and the stability of our society. I think we have an obligation to talk about it,” he recently told Roll Call.

Santorum drew fire back in 2003 for comparing homosexual acts to allowing for “man on child, man on dog” relationships.

Meanwhile, there’s always the chance that a renewed focus on social issues could hurt Republican candidates, especially among women and independents.

A University of New Hampshire poll released earlier in the month revealed that just 29 percent of Granite State voters support the repeal of same-sex marriage while 62 percent oppose repeal.

Looking more closely at the numbers, a strong majority of independents, 65 percent, oppose repeal. And surprisingly, even 38 percent of Republicans oppose repeal. Both Republicans and independents can vote in New Hampshire’s primary elections.

“I would think any potential candidate coming through New Hampshire should know that one in three Republicans and 66 percent of independents support marriage equality here,” she said. “New Hampshire’s marriage law is popular. ... People here don’t want to hurt their neighbors, co-workers and friends. Eliminating the freedom to marry is not in keeping&nbsp; with New Hampshire’s ‘live free or die’ values.”